Struct CompactDictionaryView 

pub struct CompactDictionaryView<'a> { /* private fields */ }

Borrowed, Copy view over a compact dictionary’s buffers.

Like CompactDictionary its fields are private: a value can only be obtained from an owned dictionary (Dictionary::as_view) or by validating raw borrowed buffers with validate_safety, validate, or new_unchecked.

Implementations

impl<'a> CompactDictionaryView<'a>

pub fn validate_safety( bytes: &'a [u8], offsets: &'a [u32], ) -> Result<Self, InvalidColumn>

Validate raw borrowed (bytes, offsets) for safe decoding over the same slices (no copy) — the checked door across the safety boundary. The borrowed bytes must already be read-padded (a borrow cannot be extended).

pub fn validate( bytes: &'a [u8], offsets: &'a [u32], ) -> Result<Self, InvalidColumn>

Validate raw borrowed (bytes, offsets) for safe decoding and correct search over the same slices (no copy) — the checked door across the trust boundary. The borrowed bytes must already be read-padded (a borrow cannot be extended).

Errors

As CompactDictionary::validate.

pub fn check_correctness(&self) -> Result<(), InvalidColumn>

Check correctness-only invariants on an already safety-validated view.

pub unsafe fn new_unchecked(bytes: &'a [u8], offsets: &'a [u32]) -> Self

Seal raw borrowed (bytes, offsets) into a view without checking.

Safety

The slices must satisfy the structural invariants checked by validate_safety, and must remain immutable and stable for the lifetime of the returned view.

pub fn code_bits(&self) -> u8

Minimum bits per code needed to address this dictionary, ceil(log2(num_tokens)). See CompactDictionary::code_bits.

pub fn to_wide(&self) -> WideDictionary

Materialize the WideDictionary form: every token laid out in its own fixed MAX_TOKEN_SIZE-byte row, so a decode reaches a token at code * MAX_TOKEN_SIZE with no code → offset → bytes indirection. Worth building once to amortize over a bulk or repeated decode; see WideDictionary for the space/speed trade-off.

The source view already satisfies the structural invariants, so this never validates and never fails. Two invariants carry the build:

• read-padding lets each row be filled with one fixed 16-byte copy from the token’s offset — an over-read past the token into neighbouring or padding bytes (harmless: decode only ever reads a row’s first lens[id] bytes), kept in bounds by the padding;
• the ≤ MAX_TOKEN_SIZE length bound makes lens[id] = len as u8 exact, not a silent truncation.

O(num_tokens), dominated by the row copy.

When starting from raw DictionaryStorage rather than an existing compact view, WideDictionary::validate_safety materializes the wide form directly and avoids constructing an intermediate CompactDictionary.

Trait Implementations

impl<'a> Clone for CompactDictionaryView<'a>

fn clone(&self) -> CompactDictionaryView<'a>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> Copy for CompactDictionaryView<'a>

impl<'a> Debug for CompactDictionaryView<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl DictionaryView for CompactDictionaryView<'_>

fn num_tokens(&self) -> usize

Number of tokens in the dictionary. The valid token ids are 0..num_tokens().

fn token(&self, id: Token) -> &[u8]

Bytes of token id. Bounds-checked; panics if id is out of range.

fn token_len(&self, id: Token) -> usize

Byte length of token id. Bounds-checked; panics if id is out of range.

unsafe fn token_ptr(&self, id: Token) -> *const u8

Raw pointer to token id’s bytes.

unsafe fn token_len_unchecked(&self, id: Token) -> usize

Token id’s length — the unchecked counterpart of token_len.

impl<'a> From<&'a CompactDictionary> for CompactDictionaryView<'a>

fn from(d: &'a CompactDictionary) -> Self

Converts to this type from the input type.